1. Field of the Invention
The present invention relates to a recording apparatus for recording by causing a plurality of heat generating elements to generate the heat.
Recording apparatuses which can be used in the invention include a printer, a word processor, an electronic typewriter, a facsimile apparatus, a copying apparatus, and the like.
2. Related Background Art
A thermal transfer printer will be described hereinafter as an example of a recording apparatus.
Hitherto, as a heat control system of the thermal transfer printer, a system in which a heat pulse width is controlled by using a thermistor has been known.
That is, a temperature of a print head is measured by the thermistor before printing and a width of heat pulse which is applied to the print head is set on the basis of the temperature value measured, thereby executing the subsequent printing operation by the heat pulse width.
However, in the conventional heat control, the heat pulse width is determined in accordance with the temperature obtained by the thermistor and the printing operation is executed on the basis of the heat pulse width after that. Therefore, when the printing operation is continuously executed, that is, if no white dots exists and black dots are continued, the print head is overheated, so that the heat is accumulated and sometimes printed characters become obscure. Conversely, when the heat is insufficient, the printed characters are partially broken. On the other hand, there is also a problem that erasing characteristics of the character printed when the heat of the print head is accumulated is bad.
To solve the above problems, a system in which the temperature is detected every printing operation by the thermistor and the heat pulse width is controlled is also known. However, this system has a problem in that the high speed printing operation cannot be executed because it takes too much time to detect the temperature.